130 Prof. M‘Intosh’s Notes from the 
marks the end of the shafts externally, and a small black 
speck is near the inner margin. The shafts are brown and 
of moderate length. Unfortunately the mandibles in the 
‘Porcupine’ form were broken, but sufficient remained to 
show that the dentary edge, though slightly sinuous inter- 
nally, was more or less entire. The small size of the 
example probably accounts for this variation. 
Other examples from Naples show variations in the num- 
ber of teeth on the several plates, so that the divergencies 
indicated are not of essential importance. 
The first four or five feet are larger than the succeeding, 
from the elongation of the proximal region, and this is 
especially the case with the first three, which are directed 
forward and outward, and to a less extent with the fourth. 
All these appear to be developed for special functions, and 
they are very vascular, a network of anastomosing vessels 
occurring from base to tip. The first is the longest and 
largest, bearing dorsally a cirrus of considerable propor- 
tional size, and which arises towards the tip from a basal 
enlargement. A group of slender spines, as in Eunice, 
passes through the basal segment to the cirrus itself. 
Beneath is a bluntly conical setigerous region with a long 
subulate papilla at its extremity. The ventral cirrus is 
somewhat fusiform in outline—constricted at the base, then 
enlarged, and finally tapering to the tip. The setigerous 
region is supported by two pale spines, and has superiorly 
rather stout dorsal bristles, none of which project beyond 
the tissues, but they appear to be simple with a short 
tapering region at the tip and winged. ‘The ventral bristles 
(passing below the spines) have a feebly marked articulation 
and a long tapering terminal piece, which has a bifid claw 
guarded by wings. 
The 2nd, 8rd, and 4th feet are similar to the Ist, but 
the bristles, especially the ventral, are stronger (Pl. X. 
fig. 1). The 5th foot has a branchial process of full-size, 
arising from the site of the dorsal cirrus, but so large is it 
that the cirrus appears to be a mere process of its outer 
wall. Every succeeding segment in the preparation has a 
stem, the slender spines of the region traversing their origin 
and going beyond into the cirrus for three-fourths of its 
length, in the posterior feet of the fragment. 
The feet of the Neapolitan and ‘ Porcupine’ forms agree 
in general contour, and in being double—that is, having a 
dorsal and a ventral division, as indicated by a group of 
spines which penetrate the base of the dorsal cirrus, and in 
having bifid bristles, In the Neapolitan form the Ist foot 
